“Unimaginable,” like “incredible,” is an adjective that seems seldom employed accurately. This sentence gets it about right, though:
For nine unimaginable months he was one of a group of eighteen prisoners of whom nine were shot dead each morning and replaced by nine others.
It’s from Joseph O’Neill’s investigation of his grandfathers’ (completely unrelated) internments in World War II, Blood-Dark Track. The above probablility-defier is Frank Ryan, whose life is a testament to the, uh, complexities of history.
Also, until I poked around on Wikipedia, I would have thought it incredible that, during World War II, a US invasion of Ireland was imagined.
PS hitherto reading O’Neill’s book I’d only known of Frank Ryan from the Pogues’ The Sick Bed of Cúchulainn: